Characterization of Bio‐Optical Anomalies in the Kerguelen Region, Southern Indian Ocean: A Study Based on Shipborne Sampling and BioGeoChemical‐Argo Profiling Floats
The Southern Ocean (SO) is known for its atypical bio-optical regime. This complicates the interpretation of proxies measured from satellite and in situ platforms equipped with optical sensors, which occupy an important niche for monitoring the vast and remote SO. A ship-based field study in concert...
Published in: | Journal of Geophysical Research: Oceans |
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Language: | English |
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American Geophysical Union (AGU)
2023
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Online Access: | https://archimer.ifremer.fr/doc/00868/98001/107249.pdf https://archimer.ifremer.fr/doc/00868/98001/107250.pdf https://doi.org/10.1029/2023JC019671 https://archimer.ifremer.fr/doc/00868/98001/ |
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ftarchimer:oai:archimer.ifremer.fr:98001 2024-04-21T08:12:13+00:00 Characterization of Bio‐Optical Anomalies in the Kerguelen Region, Southern Indian Ocean: A Study Based on Shipborne Sampling and BioGeoChemical‐Argo Profiling Floats Uitz, J. Roesler, C. Organelli, E. Claustre, H. Penkerc'H, C. Drapeau, Serge Leymarie, E. Poteau, A. Schmechtig, C. Dimier, C. Ras, J. Xing, X. Blain, S. 2023-12 application/pdf https://archimer.ifremer.fr/doc/00868/98001/107249.pdf https://archimer.ifremer.fr/doc/00868/98001/107250.pdf https://doi.org/10.1029/2023JC019671 https://archimer.ifremer.fr/doc/00868/98001/ eng eng American Geophysical Union (AGU) https://archimer.ifremer.fr/doc/00868/98001/107249.pdf https://archimer.ifremer.fr/doc/00868/98001/107250.pdf doi:10.1029/2023JC019671 https://archimer.ifremer.fr/doc/00868/98001/ info:eu-repo/semantics/openAccess restricted use Journal Of Geophysical Research-oceans (2169-9275) (American Geophysical Union (AGU)), 2023-12 , Vol. 128 , N. 12 , P. e2023JC019671 (33p.) phytoplankton communities ocean optics Southern Ocean BGC-Argo profiling floats text Article info:eu-repo/semantics/article 2023 ftarchimer https://doi.org/10.1029/2023JC019671 2024-03-27T15:28:15Z The Southern Ocean (SO) is known for its atypical bio-optical regime. This complicates the interpretation of proxies measured from satellite and in situ platforms equipped with optical sensors, which occupy an important niche for monitoring the vast and remote SO. A ship-based field study in concert with time series observations from BioGeoChemical-Argo (BGC-Argo) profiling floats were used to investigate spatial and temporal variations in bio-optical relationships in the open ocean waters surrounding the Kerguelen Plateau in the Indian sector of the SO. Compared to other regions with similar chlorophyll concentrations, chlorophyll-specific phytoplankton absorption in the blue waveband presented a consistent negative anomaly. The anomaly was uniform over deep mixed layers and correlated with phytoplankton size, photoacclimation and atypically high concentrations of fucoxanthin. The BGC-Argo observation-based proxies revealed that the blue absorption anomaly increased with chlorophyll concentration both spatially and temporally and, while particularly pronounced in the naturally iron-fertilized waters, was also found in the High Nutrient Low Chlorophyll region. While phytoplankton size was an important driver of the anomaly, photoacclimation associated with self-shading of phytoplankton cells was also involved during intense booms. The backscattering coefficient exhibited negative and positive anomalies in the low and high biomass regimes, respectively. The large positive anomaly in high biomass regimes was attributed to the variable non-algal particles characteristics associated with a relatively high production of bloom by-products. With clear understanding of the bio-optical anomalies, BGC-Argo floats stand as unique tools for monitoring the bio-optical spatio-temporal complexity of the SO. Key Points Contribution by large diatoms and photoacclimation are major drivers of a negative anomaly in the blue chlorophyll-specific phytoplankton absorption coefficient BioGeoChemical-Argo observations indicate a ... Article in Journal/Newspaper Southern Ocean Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) Journal of Geophysical Research: Oceans 128 12 |
institution |
Open Polar |
collection |
Archimer (Archive Institutionnelle de l'Ifremer - Institut français de recherche pour l'exploitation de la mer) |
op_collection_id |
ftarchimer |
language |
English |
topic |
phytoplankton communities ocean optics Southern Ocean BGC-Argo profiling floats |
spellingShingle |
phytoplankton communities ocean optics Southern Ocean BGC-Argo profiling floats Uitz, J. Roesler, C. Organelli, E. Claustre, H. Penkerc'H, C. Drapeau, Serge Leymarie, E. Poteau, A. Schmechtig, C. Dimier, C. Ras, J. Xing, X. Blain, S. Characterization of Bio‐Optical Anomalies in the Kerguelen Region, Southern Indian Ocean: A Study Based on Shipborne Sampling and BioGeoChemical‐Argo Profiling Floats |
topic_facet |
phytoplankton communities ocean optics Southern Ocean BGC-Argo profiling floats |
description |
The Southern Ocean (SO) is known for its atypical bio-optical regime. This complicates the interpretation of proxies measured from satellite and in situ platforms equipped with optical sensors, which occupy an important niche for monitoring the vast and remote SO. A ship-based field study in concert with time series observations from BioGeoChemical-Argo (BGC-Argo) profiling floats were used to investigate spatial and temporal variations in bio-optical relationships in the open ocean waters surrounding the Kerguelen Plateau in the Indian sector of the SO. Compared to other regions with similar chlorophyll concentrations, chlorophyll-specific phytoplankton absorption in the blue waveband presented a consistent negative anomaly. The anomaly was uniform over deep mixed layers and correlated with phytoplankton size, photoacclimation and atypically high concentrations of fucoxanthin. The BGC-Argo observation-based proxies revealed that the blue absorption anomaly increased with chlorophyll concentration both spatially and temporally and, while particularly pronounced in the naturally iron-fertilized waters, was also found in the High Nutrient Low Chlorophyll region. While phytoplankton size was an important driver of the anomaly, photoacclimation associated with self-shading of phytoplankton cells was also involved during intense booms. The backscattering coefficient exhibited negative and positive anomalies in the low and high biomass regimes, respectively. The large positive anomaly in high biomass regimes was attributed to the variable non-algal particles characteristics associated with a relatively high production of bloom by-products. With clear understanding of the bio-optical anomalies, BGC-Argo floats stand as unique tools for monitoring the bio-optical spatio-temporal complexity of the SO. Key Points Contribution by large diatoms and photoacclimation are major drivers of a negative anomaly in the blue chlorophyll-specific phytoplankton absorption coefficient BioGeoChemical-Argo observations indicate a ... |
format |
Article in Journal/Newspaper |
author |
Uitz, J. Roesler, C. Organelli, E. Claustre, H. Penkerc'H, C. Drapeau, Serge Leymarie, E. Poteau, A. Schmechtig, C. Dimier, C. Ras, J. Xing, X. Blain, S. |
author_facet |
Uitz, J. Roesler, C. Organelli, E. Claustre, H. Penkerc'H, C. Drapeau, Serge Leymarie, E. Poteau, A. Schmechtig, C. Dimier, C. Ras, J. Xing, X. Blain, S. |
author_sort |
Uitz, J. |
title |
Characterization of Bio‐Optical Anomalies in the Kerguelen Region, Southern Indian Ocean: A Study Based on Shipborne Sampling and BioGeoChemical‐Argo Profiling Floats |
title_short |
Characterization of Bio‐Optical Anomalies in the Kerguelen Region, Southern Indian Ocean: A Study Based on Shipborne Sampling and BioGeoChemical‐Argo Profiling Floats |
title_full |
Characterization of Bio‐Optical Anomalies in the Kerguelen Region, Southern Indian Ocean: A Study Based on Shipborne Sampling and BioGeoChemical‐Argo Profiling Floats |
title_fullStr |
Characterization of Bio‐Optical Anomalies in the Kerguelen Region, Southern Indian Ocean: A Study Based on Shipborne Sampling and BioGeoChemical‐Argo Profiling Floats |
title_full_unstemmed |
Characterization of Bio‐Optical Anomalies in the Kerguelen Region, Southern Indian Ocean: A Study Based on Shipborne Sampling and BioGeoChemical‐Argo Profiling Floats |
title_sort |
characterization of bio‐optical anomalies in the kerguelen region, southern indian ocean: a study based on shipborne sampling and biogeochemical‐argo profiling floats |
publisher |
American Geophysical Union (AGU) |
publishDate |
2023 |
url |
https://archimer.ifremer.fr/doc/00868/98001/107249.pdf https://archimer.ifremer.fr/doc/00868/98001/107250.pdf https://doi.org/10.1029/2023JC019671 https://archimer.ifremer.fr/doc/00868/98001/ |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
Journal Of Geophysical Research-oceans (2169-9275) (American Geophysical Union (AGU)), 2023-12 , Vol. 128 , N. 12 , P. e2023JC019671 (33p.) |
op_relation |
https://archimer.ifremer.fr/doc/00868/98001/107249.pdf https://archimer.ifremer.fr/doc/00868/98001/107250.pdf doi:10.1029/2023JC019671 https://archimer.ifremer.fr/doc/00868/98001/ |
op_rights |
info:eu-repo/semantics/openAccess restricted use |
op_doi |
https://doi.org/10.1029/2023JC019671 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
128 |
container_issue |
12 |
_version_ |
1796932195327148032 |